LAUSR

e13591 Background: Brain metastases (BM) are a significant source of disability and mortality in cancer patients. Investigations on the risk factors for their development are limited. We provide risk factors assessment using the largest cancer database. Methods: We analyzed the National Cancer Database from 2010-2014, for risk factors and survival outcomes in all patients with BM. Results: 4,650,963 tumor records were analyzed of which 88,274 were BM. Lung cancer accounted for 82.2%, breast cancer for 4.2%, melanoma for 3.5%, and urinary system tumors for 3.1% of cases. The majority of patients were males (51.6%), and whites (84.2%) with a median age of 65 years. A high index of comorbidities [Charlson-Deyo score (CDS) ≥3] was reported in 3.5% of patients. Lung primaries had the highest risk of BM (OR of 17.867), followed by melanoma (OR 1.946). Patients diagnosed at 70 years or older were less likely to present with BM, while patients diagnosed between 40 and 60 years were at increased risk. Other and unknown race were associated with an increased risk of BM compared to whites. Patients with a CDS of one or two had a decreased risk of presenting with BM compared to patients with scores greater or equal to three. Median overall survival was 5 months, with a 5-year survival rate of 5.2%. There was a decreasing risk of mortality, and increasing risk of receiving surgery, radiation, or chemotherapy per advancing year of diagnosis. Older age, white race, Hispanic origin, and higher CDS were risk factors for mortality. Conclusions: Higher number of comorbidities, younger age at diagnosis, and other races were associated with an higher risk of synchronous BM. The risk of mortality is decreasing, with a higher risk of receiving radiation, surgery, and/or chemotherapy. Median overall survival has increased in comparison to the Radiation Therapy Oncology Group Recursive Partitioning Analysis RPA studies (4.4 months).